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llvm / llvm-project / a9dff35ad251cd20376ab25b26d1e5394e18ff4c
commita9dff35ad251cd20376ab25b26d1e5394e18ff4c[log] [tgz]
authorStephen Tozer <stephen.tozer@sony.com>Thu Apr 17 17:37:42 2025 +0200
committerGitHub <noreply@github.com>Thu Apr 17 16:37:42 2025 +0100
tree5b818ed3fa180d686e0e64661c3d745cd0c69675
parent70e2acf0c5650b8862c41f2697a9e0485ecb17be [diff]
[Clang] Enable -fextend-lifetimes at -Og (#118026)

Recently, a new flag -fextend-variable-liveness was added that prevents
optimizations from removing the values of source variables in some cases,
improving the quality of debugging for optimized builds where it is
enabled.

Following the inclusion of the flag, this patch enables it by default
when `-Og` is set. Currently, `-Og` is equivalent to `-O1` - it is
effectively just an alias. By enabling `-fextend-lifetimes`, this patch
changes the code generated by Clang with `-Og` to have reduced
optimization and greater debuggability than `-O1`, differentiating the
two according to their respective purposes. This idea was discussed
previously on Discourse where there was general agreement with the
principle of this change:

https://discourse.llvm.org/t/rfc-redefine-og-o1-and-add-a-new-level-of-og
4 files changed
tree: 5b818ed3fa180d686e0e64661c3d745cd0c69675
  1. .ci/
  2. .github/
  3. bolt/
  4. clang/
  5. clang-tools-extra/
  6. cmake/
  7. compiler-rt/
  8. cross-project-tests/
  9. flang/
  10. flang-rt/
  11. libc/
  12. libclc/
  13. libcxx/
  14. libcxxabi/
  15. libunwind/
  16. lld/
  17. lldb/
  18. llvm/
  19. llvm-libgcc/
  20. mlir/
  21. offload/
  22. openmp/
  23. polly/
  24. pstl/
  25. runtimes/
  26. third-party/
  27. utils/
  28. .clang-format
  29. .clang-format-ignore
  30. .clang-tidy
  31. .git-blame-ignore-revs
  32. .gitattributes
  33. .gitignore
  34. .mailmap
  35. CODE_OF_CONDUCT.md
  36. CONTRIBUTING.md
  37. LICENSE.TXT
  38. pyproject.toml
  39. README.md
  40. SECURITY.md
README.md

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